The British model of Special Forces continues to stand out for a decidedly particular characteristic: the 21 SAS and 23 SAS, the two regiments of the Special Air Service Reserve, accept applications from men and women who have never served in the Armed Forces.

And the probably most surprising fact concerns the age.

According to the British Army, a candidate without any previous military experience can apply up to 47 years and 6 months of age to enter the Army Reserve and start the path that can subsequently lead them to the SAS Reserve selection.

For those coming from the regular British Armed Forces or the Army Reserve, the limit is even higher: the candidate must be under 48 years and 364 days old when they start the Aptitude phase of the SAS(R) selection.

These are particularly high age limits, making the British model very interesting in the debate on the age of access to Special Forces.

A civilian can apply, but does not go directly to SAS selection

However, it is necessary to clarify a fundamental aspect.

The opening to civilians does not mean that a person without any military experience can present themselves directly for SAS selection.

The British Army specifies that the candidate is initially directed to a local unit of the Army Reserve, where they must complete the Basic Military Training, the Initial Trade Training, and subsequently gain military experience before being authorized to face the SAS Reserve Selection.

The British system, therefore, allows even a person who has pursued a completely civilian career for most of their life to start a military path relatively late and, if they demonstrate the required characteristics, subsequently attempt access to the Special Air Service Reserve.

However, there are no shortcuts: before the actual selection, the candidate must be transformed into a soldier, receive professional training, and gain experience.

SAS Reserve Selection: five phases

The British Army structures the selection path of the 21 and 23 SAS into five main phases.

1. Briefing Course

The first phase consists of a six-day Briefing Course, described by the British Army as a particularly challenging assessment.

It serves to illustrate the qualities and standards required to operate in the UK Special Forces and simultaneously conduct an initial assessment of the candidate's suitability.

Those who pass this phase can proceed to the planned selection path.

2. Aptitude

The Aptitude phase lasts three consecutive weeks.

It includes a progressive series of timed marches culminating in an endurance test on particularly challenging terrain.

The goal is not only to verify physical preparation but also to observe the candidate's ability to maintain performance, motivation, and clarity under pressure and in conditions of severe fatigue.

3. Standard Operating Procedures and Tactics Course

After passing Aptitude, the candidate undergoes further training and evaluation dedicated to Special Forces tactics, techniques, and procedures.

Military skills take a central role, and particular attention is paid to the speed with which the aspirant can assimilate new skills while under physical and mental pressure.

4. Special Operations Procedures & Tactics 2

The fourth phase lasts five weeks and is common to the different selection paths.

It includes activities of Surveillance and Reconnaissance, communications, and SERE – Survive, Evade, Resist, Escape training, meaning to survive, evade capture, resist, and escape.

5. Mandatory Training

The final phase must provide the future SAS Reserve operator with the necessary skills to be considered fully employable.

The program includes, among other subjects, Tactical Combat Casualty Care (TCCC), communications, Partner Resistance Operations, Discrete Manoeuvre, Close Quarter Marksmanship, and Close Quarter Battle.

After completing all phases, candidates receive the beret and are welcomed into the regiment. Further modules follow, including Discrete Manoeuvre 2 and driving training, before being considered fully available for operational deployment.

A selection open until almost 49 years

It is precisely the age limit that makes the system particularly interesting.

A civilian can start the path in the Army Reserve up to 47 years and 6 months, while a candidate from the regular forces or reserve can start Aptitude up to 48 years and 364 days.

Of course, the maximum administratively allowed age does not mean that physical standards are reduced.

The British Army emphasizes that candidates must be capable of enduring intense and prolonged training periods, be available for overseas deployment, and commit to a concrete operational engagement.

The recruitment page also indicates, already for the Briefing Course, tests such as a 12.8 km march, a UKSF swimming test, a 2 km aerobic test, and strength and conditioning evaluations.

Therefore, it is not an opening that lowers standards but a philosophy that seems to place considerable weight on maturity, judgment, personal experience, and motivation, in addition to physical and military capabilities. The British Army itself emphasizes that, in the difficult and changing conditions in which the UKSF operate, maturity and judgment are fundamental characteristics.

A Special Forces operator is not just “a man with a rifle”

The British choice also offers a point of reflection on the evolution of Special Forces.

The traditional image of the operator exclusively engaged in direct action now represents only a part of a much more complex operational environment.

Modern special operations require reconnaissance and surveillance capabilities, communications, planning, information management, cooperation with partner forces, and numerous specialized skills.

In this context, even characteristics that generally grow with experience — maturity, decision-making ability, adaptability, and professional skills developed in civilian life — can represent a value.

Of course, there remains a concrete issue: training a Special Forces operator requires time and significant resources, and starting the path at over forty inevitably reduces the potential number of years available for the most physically demanding roles.

However, the British model seems to consciously accept this compromise, expanding the pool of candidates without altering the standards required to pass the selection.

Compensation and benefits

Economically, the Army Jobs page indicates an initial rate of £134.89 per day for a SAS Trooper of the Reserve, to which the normal incentives provided for the Army Reserve are added, including tax-free annual bonus, paid leave, and pension.

The British Army's institutional page also specifies that SAS(R) soldiers receive Special Forces Pay and Recruitment & Retention Pay. In case of mobilization, an annual salary of about £42,000 for Other Ranks and about £66,000 for officers is indicated.

Support personnel

Alongside the selected operators, members of the Support Squadron of the 21 and 23 SAS also operate.

For these roles, it is not necessary to pass the SAS selection, but the British Army still requires high levels of physical fitness and commitment.

Direct civilian access is not provided: for these roles, it is necessary to come from the regular Armed Forces or the Army Reserve, possess the required professional qualifications, and already have the necessary Security Clearance.

The indicated specialties include logistics personnel, doctors and Combat Medical Technicians, communications operators, administrative personnel, and Intelligence Corps analysts. For these transfers, the maximum indicated age limit is 51 years and 364 days.

21 and 23 SAS: the value of the Reserve model

The 21 SAS and 23 SAS belong to the UK Special Forces Reserve and represent a fully integrated component of the British Special Forces system, with a selective and training path designed to identify personnel capable of operating to extremely high standards.

And it is precisely here that the British model shows one of the most interesting aspects: it does not exclude a priori those who arrive later in military life.

A man or woman from the civilian world can enter the Army Reserve, build the necessary military experience, and subsequently face the SAS Reserve selection path. Today, this path can start up to 47 years and 6 months even without ever having worn a uniform before.

It is a choice that greatly expands the pool of potential candidates and seems to reflect a modern conception of the Special Forces operator: not only physical performance and capability in direct action but also maturity, experience, decision-making ability, adaptability, and specialized skills.

In an operational environment where reconnaissance, surveillance, intelligence, communications, technologies, information dominance, and cooperation with partner forces take on increasing importance, chronological age can therefore represent only one of the factors to be evaluated.

The British principle seems quite clear: if the candidate still possesses the required physical, mental, and professional capabilities and manages to meet the selection standards, age alone should not necessarily close the door.

And perhaps this is the most significant element of the entire system: not lowering the bar, but allowing a broader audience to attempt to reach it.

Sources

• British Army – 21 & 23 Special Air Service (SAS).

• British Army Jobs – SAS Reserve.